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Associated Press
Vice presidential candidate Paul Ryan and Vice President Joe Biden face off in their first debate Thursday from 7-9:30 p.m. MDT.

SALT LAKE CITY  — More attention is being focused on Thursday’s vice presidential debate since Mitt Romney shook up the race last week with a strong performance against President Barack Obama in their first debate.

But political observers say there’s little chance that the match-up between Vice President Joe Biden and the No. 2 on the Republican ticket, Rep. Paul Ryan of Wisconsin, will have a significant impact on voters.

“People don’t vote for a vice president. They vote for a president,” said Ohio State University political science professor Nathaniel Swigger. “The vice president is just the guy they happen to drag along.”

He said barring “something that’s really extraordinary” in the 90-minute debate at Centre College in Danville, Kentucky, the polls aren’t likely to move until after the next presidential debate on Oct. 16.

Romney, seen as scoring a big win in the first presidential debate in Denver on Oct. 3, has seen a bounce in the polls that is reversing weeks of bad news for the Republican candidate.

A new poll from the Pew Research Center shows Romney leading Obama 49 percent to 45 percent among likely voters. Last month, Romney trailed the president by eight points among likely voters in that survey.

For that momentum to continue, especially in swing states like Ohio that may end up determining the election, Swigger said Ryan will have to trounce Biden and then Romney has to turn in an even better showing against Obama.

“It really would have to be something that completely shifts the enthusiasm gap,” he said.  “Ryan can help. But it’s really up to Romney.”

Utah advertising executive Tom Love said the vice presidential debate has taken on new importance in the race. But he said that will only last until the next presidential debate.

“No matter what happens Thursday night, it will change on Tuesday night,” Love said.  “This one will be more theater, more entertainment, less substance and less impact on changing the polls.”

He said the interest in the vice presidential debate centers around Biden, who has a reputation for saying the wrong thing at the wrong time.  A scrappy debater, Biden toned it down against the 2008 GOP vice presidential nominee, Sarah Palin.

This time, Biden is expected to come out swinging to avenge the president’s surprisingly lackluster performance last week. The question is, how far will he go.

“Biden is a bit of a loose cannon,” Love said. “What happens if Biden goes off and says something, like he can, and it’s embarrassing…suddenly the Democrats down 0 and 2 in the debates.”

That likely means Ryan will be trying to bait Biden into making a gaffe, Love said, while the vice president will try to push his Republican rival into specifics about the effect of his controversial budget plan.

Colorado State University political science professor Kyle Saunders said he expects Biden to do everything he can to not make news Thursday to staunch the negative impact the presidential debate had on the Democratic ticket.

“Biden’s in a tough spot,” Saunders said, because he can’t go too far without risking being written off as making another embarrassing gaffe that could hurt the campaign.

He said the vice presidential debate definitely is attracting more attention than would normally be expected. “Usually, they’re really boring and nobody wants to watch them.”

Kirk Jowers, head of the University of Utah’s Hinckley Institute of Politics and a longtime Romney supporter, said the best the GOP ticket can hope for is to sustain the bump in the polls from the presidential debate.

“At this point, all eyes are really on the top of the ticket. There’s no way the vice president can be as positive for the ticket as the president,” he said. “Of course, the downside is always huge for either ticket.”

Jowers said no one should underestimate Biden’s ability to connect with voters, even though his folksy stories can lead him into gaffe territory.

Ryan, he said, is smart and “can be very wonky, which at times can be very impressive to people.”

But too much talk about the implications of Ryan’s budget plan, which includes offering vouchers in place of traditional Medicare coverage, could hurt, Jowers said.

Atlanta-based Republican strategist Joel McElhannon said the stakes have escalated for the vice presidential debate.

“I think they are definitely more important this year because what has happened. The race feels a whole lot more competitive for everybody right now,” he said.

Still, McElhannon agreed the debate between Biden and Ryan isn’t likely to be a deciding factor in the outcome of the November election.

“I don’t know if in and of itself, it’s going to drive people’s choices,” he said. “It’s more about enhancing the momentum Mitt Romney has right now or blunting that momentum.”

The Vice Presidential Debate

Time: Thursday, 7-9:30 p.m. MDT.

Location: Centre College,  Danville, Kentucky.

Format: Vice President Joe Biden and Congressman Paul Ryan will discuss foreign and domestic policy in the only formal debate between the two candidates. ABC chief foreign correspondent Martha Raddatz will moderate the debate, which will be be divided into nine segments of approximately 10 minutes each.

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